CVE-2025-14133 is a stack-based buffer overflow vulnerability identified in several Linksys wireless range extender models, specifically RE6500, RE6250, RE6300, RE6350, RE7000, and RE9000, across multiple firmware versions (1.0.013.001, 1.0.04.001, 1.0.04.002, 1.1.05.003, and 1.2.07.001). The vulnerability resides in the AP_get_wireless_clientlist_setClientsName function within the mod_form.so module. This function improperly handles the clientsname_0 argument, allowing an attacker to craft a malicious input that causes a stack-based buffer overflow. This overflow can overwrite the stack, leading to arbitrary code execution with elevated privileges. The attack vector is remote and does not require authentication or user interaction, making it highly exploitable. The CVSS v4.0 score is 8.7, reflecting high severity due to the ease of exploitation and potential impact on confidentiality, integrity, and availability. Despite early notification, Linksys has not issued patches or advisories, and a public exploit exists, increasing the risk of active exploitation. The vulnerability affects network infrastructure components critical for wireless connectivity, potentially enabling attackers to compromise internal networks or pivot to other systems.

For European organizations, this vulnerability poses significant risks. Linksys range extenders are commonly used in small to medium enterprises and home office environments to extend wireless coverage. Exploitation could lead to unauthorized access to internal networks, data exfiltration, disruption of wireless services, and deployment of malware or ransomware. Given the remote and unauthenticated nature of the exploit, attackers can target vulnerable devices en masse, potentially affecting large numbers of endpoints. This could impact sectors reliant on stable wireless connectivity, including healthcare, finance, education, and critical infrastructure. The lack of vendor response and patches increases the window of exposure, raising the likelihood of exploitation. Additionally, compromised devices could be leveraged as footholds for broader attacks within European networks, undermining confidentiality, integrity, and availability of critical systems.

Since no official patches are available, organizations should immediately identify and isolate affected Linksys range extender models and firmware versions within their networks. Network segmentation should be enforced to limit access to these devices. Disable remote management interfaces if enabled, and restrict network access to the devices to trusted administrators only. Employ network intrusion detection/prevention systems (IDS/IPS) with signatures tuned to detect exploitation attempts targeting this vulnerability. Consider replacing vulnerable devices with models from vendors providing timely security updates. Monitor network traffic for unusual activity indicative of exploitation attempts. Maintain up-to-date asset inventories to track vulnerable devices and apply compensating controls such as enhanced logging and anomaly detection. Engage with Linksys support channels for updates and advisories, and prepare for rapid deployment of patches once available.